you could flip it in the air, It'll slow down your stropping and might add to the risk of nicking the strop or rolling the edge. Keeping the spine in contact at all times give you a solid reference for the flip.
The tape to hone should be electrical. For the stropping any tape will do. The acid test for seeing if this is needed is pretty simple. Get a scrap of leather or an old belt and do 200 laps without tape. If you don't get any scratching you should be fine to take it to a strop without the tape. Also if your using a cheap strop like a whipped dog poor mans special that you don't mind damaging then just go straight to the strop. If it starts to scratch you know the solution. And provided your paying attention then you should only do minimal damage if any.
I don't think you can go wrong with either blade but the Bismarck is worth the new price, A regular 6/8 full hollow vintage razor in good condition from the bay should give a comparable shave to the dovo, and you should be able to get a vintage blade for under £30 in great condition. The 6/8 full hollow is probably the second most common razor size after 5/8.
With that in mind and since this will be your second razor the next logical step would be learning to hone. You have 2 razors in rotation, so picking up a couple of gold dollars and a cheap king icebear 1K/6K wetstone and learning to get an edge on those blades will set you up to be able to get all the 6/8 full hollow blades you can dream of off the bay and sort them yourself.