I bought the Show Chrome full cover and have not used it once. I test fit it and it does work well.
I also park in the garage every night so no cover needed.
However, at work I am in a parking lot.
When I bought my Spyder used, for some reason it came with a BRP RSS cover. Believe it or not this works great! Perfect for keeping the sun off the bike and when I come out to go home in 90-100F sunny weather, the bike is never hot and cooking especially the trunks and saddle bags which the 1/2 cover is no good for.
My Spyder is black and just cooks in direct sun. I measured 130F in my rear trunk one day when I went to the store and parked for all of 20 minutes. Not good for things kept inside there!
It's light weight (not good for keeping rain out) and goes on super easy.
Every morning I put it on in about 1 minute.
All I had to do was make a hole for the antenna in it and reinforce the hole so it did not rip (use a canvas grommet)
It covers the entire Spyder except for the front fenders. It has an elastic edge that just pulls over and fits great!
So this RSS cover that came with my Spyder RT, after about 3 years in the sun every weekday, it is finally starting to come apart at the seems near the windshield.
I like it so much I bought another to replace it.

hyea:
I personally do not like the 1/2 cover for the RT.
This is the cover I am talking about. I know it looks like it wont fit the RT but it does again except for the front fenders. It goes around the front of the frunk and around the bottoms of the saddle bags and rear fender license plate light lip. This keeps it secure in winds up to about 15 MPH or so (So Cal has daily afternoon winds that average this speed). I have never come out and found it blown off the bike.
BRP# 280000338
http://www.ebay.com/itm/NEW-GENUINE...Parts_Accessories&hash=item19f949b9c9&vxp=mtr
Bob