We've owned our Mobile Suites since August 2004. When we bought it, there were no Select Suites or Elite Suites - Mobile Suites was Doubletree RV's only product.
Excels, being wood frame RVs, are susceptable to rot, and they've had a lot of them with water leaks and rot problems discussed in the Excel owners' forum on iRV2. I have nothing against wood frames in general - I owned three wood-framed Jayco Designers - but they had better be watertight, and the Excels don't seem to be.
We've had excellent service from our MS, especially since we upgraded the wheels and tires to 17. 5" load range J Michelin XPS. That eliminated the Goodyear G614 RST tire problems. There aren't any on the market that I would be interested in moving to as ours still serves us just fine.
Rusty