I have 4 derby doubles, allows me to run a triple for two dogs and have help in the "tough" gun if needed. I train alone a lot. Mine have been very reliable. Had a problem with one not work at over 200 yards, sent in th reveiver and the transmitter and got them re-synched and now work great. I have kept up with the upgrades that I think are very reasonably priced.
I have two of the newer Derby Double's and really like them. Much improved over the older versions. The new servos and triggers are much more reliable.
The only problem, and I think it's a BIG ONE, is the new "smart bumpers" that they have swithed to are terrible; VERY fragle. The shell started cracking after only a dozen retrieves (and no I don't have a hard mouthed dog). Before long the tops w/ ropes broke off. BB's was nice enough to replace them and they said they fixed the problem (supposedly bad chemical mix in the plastic) and sent me 4 new ones at no charge. I took their word for it and bought 4 more for spares. Still cracking up very fast. Have since switched to other bumper manufacturers.
Can you believe it my charger took a [email protected]# today and I need to get another one...Oh well not bad for 4 years I guess...I probably dropped it a few times... $30.00 for a new one and they shipped it out right away...They are on the ball....
As for the bumpers I keep the nylon covers over them and it seems to keep them in good shape..a few are shot...for what reason did they give you new ones?
The canvas retriever-r-trainer bumpers with streamers work well, are lighter giving a bigger throw, and seem to last longer and are a little cheaper. If you take the BB bumpers when they are brand new, and wrap them with (white, flo-yellow, or whatever) duck tape, they'll last a LOT longer. Also, I've found using only Green loads helps them last longer as well. The yellows seem to have a little too much punch. Plus add a lot of stress to the units themselves.