I own a GWS Tiger Moth 400 and have flown the Dynam YMF 5D Waco.
The GWS is smaller (38" ws), lighter (24oz), kit build that you can install several power sources and mods......it's also a swept-back bipe.
The Dynam Waco is obviously much larger (55oz, 50"ws)......and not
a swept-back bipe.
Based on the spec's of both Dynam's......they appear very similar in weight, wing span, length, motor size, prop size, battery size ect......
Having flown both swept-back and straight wing surfaces, the only difference I have found in performance is the roll-rate, invert stability and aileron response. This is due to the Waco having dual
aileron surfaces. Where as, the Tiger Moth ailerons are longer and bottom wing mounted.....not quite as much authority and response, but still very nimble.
Either of your choices can be flown tame or radical and have very stable glide characteristics (good for slower landing and approaches).......the wheel pants on the Waco will be an issue in grass!
Personally, I like both planes, as far as bipes go,.......just depends on what your expectations will be as you get further along with your pilot skills....