Thanks everybody for your comments, I really appreciate it. (I am serious, and not being facetious).

I will explain my logic. My intention was to put together a plane for Senior Pattern contests this summer which contests use pre-1976 planes and has a max 4-stroke engine displacement of .91, and no supercharging allowed. I was going to buy something like a World Models Intruder or get my old Curare flying again. A friend had a need for a YS 1.10, mine wasn't doing anything (sat in the box for a year), and he made me an offer I couldn't refuse. I traded another unused engine for the Magnum, so it didn't really cost me anything. I thought I was all set.

My plans changed. I am going out of state to work for the next couple of months, and then will move across the country (exactly 3,283.75 miles to be accurate) at the end of the summer. The new location doesn't yet have a chapter of SPA, but has an active IMAC and AMA/FAI pattern communities with combined total of 15 or so contests a year within driving distance. I want to spend more time flying the current patterns to compete without risking my more expensive/delicate 2m plane. I wondered if my current stable of engines would work.

For the sake of continuity, please ignore the word "Magnum" in this thread. It is completely irrelevant, as I could have just as easily said "OS", "Saito", "Enya", or "No-Name Brand". I honestly don't have anything against YS engines, in fact I truly like them. I just want to know which planes will fly VERY WELL on a 90 4-stroke. If I buy another YS engine, it would be a new 1.40 sport for my light 2M plane. I don't really have a need for a smaller engine at this time, and want to spend as little money as possible.

Of course I forgot about the Runaround. It would be phenomenal on a .91, as it is 740 squares and under 7#. It may be a 25 year-old old design, but it was FAR ahead of its time. I just don't want to build right now (my plane is ARC). Already paid for, but requires another 30-50 hours of work, covering, and all hardware (maybe $60 or so plus my labor?).

As I see it, the Venus II seems to be an excellent plane (for an ARF) with a good reputation. It will certainly require a 1.20 of some sort. It has the largest wing area of the bunch and is also the heaviest by at least a pound (read="durable"). 8.5#+. $220 from LHS.

The Hyperion Helios looks to be an excellent plane, but might be marginal on a 91? maybe around 7.5#. $359 shipped from ALLERC.com

The Sebart Angel S is gorgeous and seems to fly very well. It is smaller and likely isn't stressed for a nitro engine this large (perfect for a YS 63). Weight is likely around 6# plus a few ounces. $299 shipped from fedonaircraft.com

The Fliton Inspire 90 looks great, flies great from what I have seen, and likely will fly well on a 91 because it is quite light (10 - 15 oz less than the Venus II). Empty weight is 70 oz, so I calculate 83 oz RTF including servos and pushrods, minus electric motor and battery, so add another 25 oz for engine and mount, and another 12 or so for fuel tank, throttle servo, and flight pack battery (being generous), for 120 oz. Total weight 7# 8 oz. $299 shipped from Chiefaircraft.com.

I don't know much about the Focus, but it looks very nice. I will probably save 7 oz over the weight with the YS 1.10. 7.5# to 8# range sound correct? $400 shipped from Piedmontmodels.com, $350 shipped from Centralhobbies.com

My rubbish bin Magnum gives me essentially unlimited performance on a 7# plane (I get just over 9300 rpm on a 13.5x9 APC on 20%, a little better still on 30% heli), so I hope to stretch it a bit. That calculates to 9.6# of thrust and 69 mph efflux velocity on Pe Reivers excellent calculator.