All Biotars are East German, unless you count the early Exacta mount ones but they were made in the same factory under the Third Reich

Surprisingly the CZJ T (coated) Biotar is less prone to flare than my current Helios which is in excellent condition.
Well I own an Exacta Varex IIb with an f2 Pancolar as well as two Praktina FX cameras with a 50mm Tessar and the 58mm Biotar. the build quality of the Praktina s is superb but we are talking 60+ year old cameras so best seen and handled or from a highly reputable seller.
Th early lenses for Praktinas are pre-set, my two lenses are semi-auto, you pre-cock the lens which opens to full aperture then it stops down automatically on the first pressure of the shutter release which works well.
The reality was I had a really nice Praktina with a Tessar, wanted a Helios 44 for a project but they are getting expensive dealers are buying cheap Zenit Es then selling the lenses for far more than the complete camears, bodies get scrapped. So at the camera fair I go to Helios lenses are often f50-£60 and many aren't in the best condition. A dealer who has a stall (and a shop as well as onine store) had a Praktina FX and Biotar on his web site, I'd seen it at a previous fair but by then had checked out typical copleted sales prices so knew it was a bargain,
My current Helios was on another dealers stall out of interest I asked the price, he picked it up and pressed teh aperture pin, then said a price£40 or £50 then said oh it's got a sticky aperture £5, actually it's fine
In this country good Zenit E's can be found really cheap at car boot sales, I guess Garage sales in the US.
Ian