I have experience with the tree but not in your zone. Great spring color, not bad fall color, blah summer color.........more bronzey green than anything else. Not as hardy as some JM's but hardier than some others. How's that for being rather nonspecific?? LOL!

Seriously, you will see more hardiness info on cultivars like Bloodgood, Osakazuki or Sango Kaku or many of the dissectums simply because they are sold in far greater numbers across a much wider range of climates. When you start getting into the less well-known or widely sold/planted cultivars, then the info is lacking as most of these tend to be localized into the milder zone 7&8 so-called "ideal" JM climates.

I'm near you, but closer to the lake in 5b.

I always check with Davidsans and Topiary Gardens (online sellers) before trying a new or rare cultivar. Davidsans is 5b/6a and they say:

"A very hardy reliable bright red open Jm that does ok in sun but can
take the cold also . it doesn't much like wet areas and tends to be a
slow grower but is a nice medium to small red upright . I don't see it
getting anywhere near 12" here in many many years but in friendlier
confines it may get even bigger."

http://www.davidsansjapanesemaples.com/shop/product/oshio_beni

That would be enough for me to try it in 5b, but if you want to really check then try calling Diana at Topiary Gardens and asking her experience with it (if any). She's in 5a.

Also, is there anything you have that bumps your zone at all? A warm spot you can plant it, more than average wind protection, an urban landscape temperature bump? If so, then you might be good.

I've had very good luck with all my cultivars except those with bright bark (Sango Kaku, Bihou, Shidava Gold, etc.). Have you looked into Japonicums and Shirasawanums? Really lovely Japanese maples, with better cold hardiness. If I were in 5a or anywhere even more borderline where I am, I'd be concentrating on those.

Diana does grow it: http://www.topiary-gardens.com/store/index.php?main_page=product_info&products_id=57

When I was trying to decide on a cultivar she was so helpful-- it was great to know what her trees experienced. Some cultivars she has in the field as well as in more protected areas, so she'll be able to tell you how to plant for the best performance.

I planted Oshio-beni about 15 yrs ago in front of my south facing white house. It is in a very hot spot and gets sun all day long and it handles it great. I live in zone 6, northern Utah, so it's a little warmer here. Here is a couple of pics taken today (not the best pics since I took them in bright sunlight). Overall, it has a reddish orange color during the summer.

Btw- it has been very hot here so far this summer, 100 degrees or more for over a week now :(

All, thanks for the feedback!

Nice looking tree, surprised to see that nice color. The plant I got was very different but the little new growth it had looked like the tree pictured.

I ended up taking it back as to GG's point from I found it was cold hardy but not as cold hardy as others. On the otherhand I have 'Orion' and 'Orangeola' both of which are not supposed to be 5a hardy. Although quite a bit of damage they both survived the winter of 2013/2014.