Good choice...the 4 channel version I hope Is it this version?
2 Stroke will suit you, as a complete beginner, better than 4 stroke. There is generally less to go wrong, and £ for £ you will get better performance from it. Generally speaking, 4 strokes will swing bigger props, slower...ideal for scale and warbird type models, they are generally perceived as quieter due to the lower revs, but do require a little more experience and maintenance than the simpler "no valve / tappets" 2 stroke.
There are several perfectly acceptable "cheaper than OS " type 2stroke engines available these days such as SC or ASP ( the same engines anyway ) but of course, if money is no object, then OS have a deservedly fine reputation. I have only 3 X IC powered models left in my fleet these days, an SC 91 FS in a Spitfire, and a smaller 52 2 stroke in a Wot 4 - both perform excellently.
I also have a redundant nearly new Thunder Tiger 42GP which is also fine - would power your Uno Wot great !
( Message me if you want it.
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