I have already run 2 5K races before I got injured and did very well for my age group. I am not really interested in 10K, as I know I can do the distance already. Half-marathon and more is where I find the challenge for myself.I think you should also try to race a few shorter runs. (5k, 10k etc). I routinely run with a belt with keys, eye drops, and two 10 oz bottles of water. That's just for training, and runs anywhere from 3-10 miles. Races wind up being far different than training runs. Most of the time I don't really need to touch the water, but I want to be used to carrying the weight, and practiced at drinking from the bottles - I've choked a few times from the bottle, but also had trouble drinking from cups on runs. For that matter, there's nothing worse than just needing to rinse some dust out of your mouth, only to discover that you grabbed the sugary drink that's now dripping down your face and body.
My longest race to date was 15k, and I ran with only my phone in an arm band. I skipped all the water stations and two rest stops being completely focused on maintaining my goal pace, starting at 8 min/mi and finishing 9:07 average.
Plus, lets face it, runners are a bizarre lot, but much better than cyclists. You'll never hear the end of how much a noob you are running with a camelpak.
I have been practicing using the hand-held bottle at times during training, so I can get a feel for it, even though it wasn't necessary.
You are right. Race day isn't like training day. There is usually some quirk or unforeseen circumstance that skews things a little.
Any person that judges me for wearing something during training or race day that I may feel needful in some way, that he or she finds silly (not dangerous mind you) etc. can go pound sand, as far as I am concerned. If I let such drivel bother me, I wouldn't have much self worth.
As I work my way forward to where I was prior in training, I don't see myself using a Camelbak (should I get one) all the time in training for this half-marathon. But, for those times where I have gotten a lot longer in my mileage and off by myself (or with a friend) on the trail, having more than a 21 oz bottle may certainly come in handy, for a variety of reasons, especially with training for full marathon, ultra and the like.
At this point, I am still in the intel gathering phase, and continually accessing my ongoing performance and potential needs, as it relates to ongoing trail running racing not just for this race, but the longer ones to come.
Granted, one can read some reviews on Amazon about Camelbak usage. However, I feel that asking a large audience (with varying levels of background, usage and needs) in a more personal setting such as this, can better assist me in my research. I just don't want to be down to the wire (as it were) having to consider an essential element in running, that should have merited earlier focus.