Recumbent - Rans X-Stream 26 vs X-Stream

Every passing day I'm getting closer to the day I by my first recumbent. Probably still a year or two away but getting closer. As of right now, with all the reading I've done I think the X-Stream is the bike for me. I do want to take multiple recumbents out for test rides, but for now it's the X-Stream. Two years ago I was also high on the Rotator Pursuit, but, unfortunately Rotator is no longer making bikes. The Pursuit seemed like a nice bike to me. It's the only recumbent I've ever ridden, and that was only for a few miles. For reference, my current ride is a 1988 Trek 830 mountain bike. A classic I refer to as old ironhorse. It is very sentimental to me as I bought it new with hard earned paper route money.

Anyhow, how would you folks rate the X-Stream 26 vs the X-Stream. If I understand correctly, the real difference is in the wheels. 26" wheels vs 650. According to the Rans website the 26 is 4 lbs heavier. Is this mostly due to the wheels or are components also heaver ont he 26. What are the advantages of the 26" or 650 tires? Do 26" wheels offer wider tires? More tire selection? Are 26" wheels/tires more durable?

Any experiences and/or advice you folks can share would be appreciated.

26" wheels/559mm tires many more choices, both width and tread design.

650x23 limited to "racing" types for the most part. Narrow, high pressure and fast.

I bought a stratus last year and an Xstream off ebay this year. Xstream 650x23: faster, quicker, 10 lbs lighter than my StratusXP, more aero. It came with a fairing and carbon crankset and a Zephyr seat. I used it yesterday to ride my age 58, against an ene wind of 10-12 mph, 38 miles north and 20 miles west, in just less than four hours.
Go to the Rans website and read some of the "In The Ride" articles written by Randy Schlitter owner of the company about differences between different bikes.

The X-Stream 26 comes with the same wheels and tires that are on my V3, which is the model displaced by the X-Stream. The Jet Set wheels are robust but not light. The Primo Comets are 1.5" wide and, in combination with a long frame, will minimize the effects of rough or irregular road surfaces.
X-Stream 26 owners could always replace the wheels and/or tires with lighter, zippier models. There is no lack of 26" tires to choose from. As mentioned above, not much choice in 650c tires and most are light skinny and fast but not necessarily rugged.
Why is this such a long-range project? Funds?