I too was not given a choice about brands or types. My doc originally told me it would depend on my use of my trial unit. Since then I have had 2 other units installed and 1 new set of leads due to a fall. My doc has actually asked me to research boston units (I have a medtronic unit) and let him know about what I think.
Yes my device site will get warm at times but I have found this is worse if I let the battery get more run down and have to charge it for longer periods of time.
Hope this helps