So I am not piping expert , and would love to get better at it- so i invested in a Wilton tip kit ( like 50+ tips and some flower nails and some couplers) and also got some reusable Fat Daddio's piping bags.
trouble is, the bags seem too stiff and thick , and well, they ain't working with the couplers/tips! the couplers wont even catch the threads from on the opposite side.
either I am seriously more braindead than I thought, or these bags ain't working for anybody trying to use wilton tips.....
so any suggestions?

I am trying to stay away from the disposible type bags while I am trying to just practice.... (plus reusable is slightly more eco friendly)

I totally know what you mean about the bags. They make them so stiff so that they'll last longer. You just have to cut the end so the coupler sticks out some and put the tip on and push down while turning the coupler top. It won't be easy the first couple of times. Once the bags get used some, they'll break in. You'll get the hang of it. Just practice

I haven't tried the FD bags, but I love the Wilton Featherweight bags--NOT the vinyl ones (they're hideous). They last forever and are easy to wash.

I've bought lots of mixed sizes off of Ebay and they should last me another 20 years, or so.

http://cgi.ebay.com/30-wilton-cake-decorating-bags-featherweight-assorted_W0QQitemZ150402488464QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2304afd890

HTH
Rae

not sure about all these types of piping bags but i buy the plastic disposable ones you mentioned which i find good but i don't throw them away after one use, i just make sure i give them a good wash after each use and re-use them again and they are fine!