Here are some models I'm considering. One of the difficulties I have had is separating true opinions from "buzz" paid opinions. So these reviews are mostly on opinions, not on fact.
Here are the top contenders I considered for the project...
TERRATRIKE-CRUISER
The good
It's a tadpole which means there is no need for a differential for the rear wheel. So, hill climbing power should be straighter than a one-wheel drive delta. The bike also gets very good reviews on quality. Reviews on durability suggest that it would be acceptable in this category as well. Should I decide to do the easy thing of getting a velo kit for it, they already exist. Parts availability appears to also be very good. Perhaps that's why it gets awards as a top selling bike.
The Bad
Being a tadpole, it's low to the ground so roadway obstacles may be an issue. Also, the front gear telescoping pole is not adjustable so unloading it on Craigs list or ebay becomes difficult. There may be telescoping sections that can be added on but that's unclear. There are other higher and lower models too. Overall, it looks like a nice line of bikes with the cruiser being the upper end of what I'm willing to put toward this project.
The Ugly
Price. Not that it misses much on this.
ACTIONBENT - TRIDENTThe good
This model seems to have a large gear range, larger than normal ground clearance, a mesh seat and disc brakes (important for wet driving). Having the ability to fold also might allow me to transport it by car if I want to ride it in another location. It also has an adjustable front extension for different sized riders. Being a folding trike, it's shipped in a mostly assembled state so putting it together should be rather easy. If I time my bid on Ebay properly, I can have all this for around $1200 with free shipping!
The bad
Of course, it's low which makes it not able to be seen in traffic as easily as a delta. As for overall value, this is hard to tell. It is a rather new model which may account for the lack of opinions. It's only sold over the Internet and is not shipped assembled so there is a potential for some shipping damage. Also, there are no retail dealers (ebay and 2nd hand market are the only distribution channels) so there is no way for me to test drive the bike. However, never having tried a tadpole, I doubt I would miss the "perfect fit" that may be eluding me.
The Ugly
There have been some customers who have reported glowing reviews while a few customers appear to be very unsatisfied. However, these customers apparently seem to be few in number. Due to these concerns, ordering such a bike is a risky but possibly very rewarding thing to do.
AMERICAN TRI-CRUISERThe good
Hey, it's made in America! The trike seems to be very customizable with the manufacturer willing to do modifications as requested. One such modification can be seen in the rear, is a platform one customer had since they wanted their dog to go for a ride too. It also is one of the highest tadpole designs giving both good ground clearance and a few more inches of visibility from other cars. Reviews are few, but generally good. It's apparently heavy construction also should be able to allow modification to being a velomobile easier than other tadpole models I've seen. At first glance, it also has one of the lowest initial base prices too.
The bad
The first thing I noticed was that it appears to lack camber and caster on the front wheel steering knuckle. It's hard to tell from the photos, but I would think this would make the trike a bit harder to turn since wheels would need to skid somewhat in turns. Also, the padded seat may appeal to some riders but I think I would prefer the mesh for better ventilation.
The ugly
The base price $799 doesn't include much. A more realistic price with options I would want such as front disk brakes, adjustable pedal boom, cargo shelf, dual stick steering, full gear range, fenders, "tuff frame" and shipping makes a more realistic price of $1984. In spite of a tricked-out version of this bike likely being best for this project, it is beyond my budget right now.
SUN - EZ-3 Delta
The good
If I was going for a Delta, the SUN family of bikes would probably be the way I would go. The EZ-3 entry level bike or similar model seems to be what was used in making a "rain shadow" type of velomobile. It appears to have high traffic visibility, good ground clearance and the option of having low gears installed for better hill climbing. Although not domestic, parts availability appears to be very good through the dealer network. It is also one of the few trikes that can be test driven by me before purchase. Different riders can adjust the seat forward and backward. Also, at only $899, it is affordable. The EZ-3 AX is one up from the base model at around $1400. It has an aluminum frame plus better components and a somewhat safer design. It can even sport a front mounted hub motor! An under seat steering model is also available (the EZ-3 USX) which has no handle bars in front. Instead, steering is done under the seat. That probably would be a better layout for what I'm trying to do.The bad
It's primary advantage, price, is eroded by shipping charges (or just gas, sales tax and a lost day driving to the nearest dealer if I fetch one myself). Having two wheels in the back probably makes it go up hills a little unevenly since power looks to be applied only to one rear wheel instead of both. Even with no faring, these are heavy trikes. That means a low top-speed. The large size also means transporting it via car would be problematic.
The Ugly
At speeds above 20 mph, handling has been described as unsteady to unsafe. I can imagine any velo structure I built on top would probably magnify any handling problems that existed. Also, the low price under seat steering model can take a smaller faring but it costs more money. The EZ-3 model is quite heavy (at 67lbs) and is not a folding model. The EZ-3 USX, which is the underseat steering model, also is quite heavy but has a folding feature. However, folding it doesn't appear to reduce size enough to be useful. So, future transport of any of these deltas could be a challenge.
