Ideally, you only want ones that have had sufficient colostrum in the first 6 hours of life. You'll get some losses anyway, but moreso if there are lambs with dubious early histories.
For safety's sake, it's probably a good idea to vaccinate (Heptavec-P or similar) all bottle lambs at about 3 weeks old.
You'll find gazillions of threads on here about feeding, and not overfeeding, and causing/avoiding/curing bloat in, bottle lambs.
Basically, if they're bog standard commercial white lambs, start by following the instructions on the lamb milk packet. Introduce hay or straw to chew on within the first 7 days for optimal rumen development. Offer fresh creep (or just small lamb pellets, not specifically a creep feed) from around three weeks, just small quantities, and remove after a few hours or if soiled.
There's no reason a bottle-reared female can't be a good mum; they can be prone to being overfat, which is bad for conception and worse for lambing, but if you manage them by condition scoring, there's no reason they need to be fat.
The lambs I bottle rear here go on to fetch the same at the mart, and grade as well as the others if sent deadweight - so there's no reason you can't produce good fat lambs starting with caddies. Might take a wee while longer - don't try to rush it, that's what causes the problems

And the other problem, which makes farmers irritated with the pet lambs, is how tame they are - they run up to you, climb on the quad bike, into the trailer, won't run away / be driven. If you start your flock with tame lambs, you can just call them and they'll come running - how easy is that?!