Started at a time of 31:37 but got it down to 29:15 on the second last night was on for 28:59 for last on of the last season but fell short due to a tractor pulling out and going slowly with traffic coming the other way to.
@zizou speaks a lot of sense there (in his post above)
Also things like "owning the road", by that I mean say you've got a roundabout coming up, get over to the middle of the road just to the left of the middle white lines early enough so that no bugger in a car can overtake you and then stop in front of you as they hesitate to enter the ROB, remember to look over your shoulder to check (lifesaver) as there could also be another rider about to overtake you.
If a car does overtake you like they did me just as I was entering a village and then immediately slow down to a snails pace then overtake them if it's safe to do so, don't sit behind if you are quicker than them. Obviously don't break the law but ride clever and safely.
I think wheels really come into their own on some of the faster dual carriageway events and longer distance courses but on the more "sporting" (hilly) courses that's a lot of money for little gain. I would think you should be able to get down to 24- 25 minutes on a 10 even with a roadbike with tri bars with skinsuit shoe covers, if you're any good (Obviously depending on the course).
A good indicator of how you're doing on a particular 10 course would be how far off the winners time you are on the night, so for me my best last season was a 23.55 and the winner was 22.33 on the same night, I was on my my TT bike as in the pic in a previous post.
The season before, my best was 24.29 on my roadbike with tri bars, skinsuit, shoe covers helmet etc, and the winning time on the same night was 22.45.
Obviously ours is a small club and we don't very often get pros turning up, although it did happen last season when an ex pro clocked 21.28 and a new course record!
Basically if you are getting 28- 29 minutes and the winning times are similar to the ones I've been describing then seriously save your money, you've got at least 4 minutes to find first.