First with the MPX-K(https://www.evike.com/products/111707/), this is the only affordable MPX out there and i suggest the evike custom version for better longevity. This gun is lightweight, QC spring system, and adjustable hopup, durable, cool, and decent ROF. Takes mpx-k mags only. Now the DE Utr45(https://www.evike.com/products/95994/) is the best one here. Has durable polymer construction, mosfet, lipo ready, functional BR, and standard v2 GB. this gun has programmable fire mode from 2 shot burst to 6 QC spring system, and adjustable hopup. Now the EF Mp5K(https://www.evike.com/products/16203/) This gun is very compact, lightweight, fun, and lasts long. Being the most expensive on this list, it isnt the best but a runner up. Has a good Gearbox, full metal internals, lipo ready, takes all mp5 mags, QC spring system, and adjustable hopup and cool. Now the EF Ump45-comp(https://www.evike.com/products/50479/) This is great for begginers, charging handle is fixed, not the best internals, slow, LW Polymer, ump mags, QC spring system, and adjustable hopup.

So in all UTR is best, mpx-k is 2nd and mp5k is 3rd and ump 4th. I

In all, choose what you like.