Does anyone have any experience with side entry bottle cages?
I was looking into ordering a pair for a 44cm Cannondale since the top tube is too close to the typical bottle cage. It is very difficuly to get a bottle in and out.
:D

I have no experience with that but IMO if you are having trouble w/your current configuration- I don't see how adapting to a new system will bring you any more pain than you are currently experiencing. :)

Problem is, Im planning a 1/2 IM later this year and need to carry more than what I carry for shorter races. Currently I just pop on the trusty Aero Drink.

The location of the bottle cage mounting bolts renders them useless for a bike with such a small frame. Another alternative is something like the X-Lab Flat Wing (or similar) but Ive had one too many botles ejected so am looking for another alternative.

I'm in the same boat...1/2 IM in August. Looked at several options to accompany my aero bottle, too. You could try the Aquarack, which has rubber washers that hold the bottles pretty tight. I tried one out on my bike, but didn't like the fit/location. XLAB makes the Saddlewing and Flatwing, you add your own cages. I have Specialized Carbon Cages, which have rubber pieces attached to hold the bottles pretty well. A friend ended up giving me a Saddlewing for free, which is just the right price.;) I'll add my cages and some XLAB straps to hold my CO2, etc.

sidewinder cages = great!
if you can get them both in there (44cm is pretty tight!) i know they work like a champ on my 51cm frame