Digital BW, The Print

I've been using and refilling the MIS bottom fill cartridges with UT 
ink for my 1280.  I just received some top fill carts from Media 
Street and the syringes will arrive on Monday.  The top fill carts 
require a syringe needle that you insert through a hole in the top.  
The needle goes to the bottom and you fill slowly to avoid bubbles 
according to the instructions.  After it's filled there's a small 
stopper to plug the hole.  Has anybody used these?  Any 
advantages/disadvantages?

Thanks,

Tom