I just picked up a Huawei E587u-5, it has more frequencies and is meant to be faster than other devices out there.
But... I had a hard time getting it going, and even now I have it configured, it seems to have a harder time getting connected to my sims (Roamline, Abroadband, Tru) than my older wifi Zoom We3g or my old Samsung Galaxy S Vibrant, which still is the easiest option for a wifi hotspot.
The Huawei can take 4-6 mins to find the network, will say connecting for ages, then disconnects and tries again.

(My S2 won't work unless I pay for the tethering plan, and I've tried Foxfi and other apps, but none work, only USB tethering)

tried out my new E587u-5 on a Baltics cruise, I do like the info it gives you on the LEDs compared to my older Zoom We3g. It was fine for Roamline and Broadband, though slow to initially get going.

But for the O2 sim I was using for data, my old Samsung Vibrant Galaxy S was better, as I got texts telling me when to pay another 2 pounds for another 15MB. The Vibrant worked everywhere from Russia to European countries, with speed adequate even for VOIP.

I agree with Andy's suggestion. I have a TP-Link router with a USB port. The router is pretty tiny and runs off USB power or off AC. No battery, but I find I always run off AC so I don't want a battery to be deteriorating.

I can put in any data stick I like that it supports and off I go.

Recently I just updated my data stick from HSPA+ to LTE and it was just plug and play. No reconfiguring necessary, even. It just worked.

As a bonus, my router has a wired port too which is nice to use if I work close to the router. You could hook it up to a switch if you needed more ports.