iPhone SE (and other iPhones) LTE Bands for US & EU

Questions:

1. Will the default sim-free A1662 work well in EU (Germany, France, Sweden, UK) despite it not having Band 7?

According to this article:

http://www.theguardian.com/technology/blog/2012/mar/28/4g-broadband-uk-how-fast

Essentially, there are two groupings: high frequency (2600MHz) or low frequency (in the UK, 800MHz). Low and high frequencies have different characteristics: low-frequency signals are better at penetrating walls, but high-frequency ones can carry more data in a given time.

2. Is it possible to buy the A1723 model unlocked here in the US somehow? Are all the LTE Bands listed below active on the US A1723 models?

Details:

I'm from the US but I'll be moving to the EU for two years. When I look at the LTE Networks in Western Europe, it seems the 3 most common Bands are 3 (1800 MHz), 7 (2600 MHz), and 20 (800 MHz).

https://en.wikipedia.org/wiki/List_of_LTE_networks_in_Europe

The new iPhone SE has two models with the sim-free model being A1662:

1) Model A1662 - LTE (Bands 1, 2, 3, 4, 5, 8, 12, 13, 17, 18, 19, 20, 25, 26, 29)

AT&T, Verizon, T-Mobile, etc.

2) Model A1723 - LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 17, 18, 19, 20, 25, 26, 28)

Boost, nTelos, Sprint

iPhone SE

http://www.apple.com/iphone/LTE/#iphone-se

http://www.apple.com/iphone-se/specs/

Note: I currently have the iPhone 6s (which has all 3 EU LTE Bands) but I don't like the size and thus I will be downsizing to the SE.