Originally Posted by
downinit
If the price is the same or close, always book with the operating carrier.
Bad advice. As has already been stated, UA has much more generous change policies than LH. For me, this makes it a no brainer to book through UA.
Originally Posted by
downinit
In case of IRROPS, you will be in a much better position to reschedule flights if you booked via LH.
Not true. Day of departure, LH will be responsible for rebooking, regardless of ticketing carrier. And because it's a UA ticket, UA will also be able to rebook. So in case of IRROPS, you'll have a choice of dealing with LH or UA. Personally I prefer dealing with UA, though there may be times that it's advantageous to let LH handle the rebooking.
Originally Posted by
downinit
For quite a few years now, I have had nothing but nightmares trying to manage TATL flights on LH-group airlines with an 016 ticket.
Originally Posted by
angetenar
In all of my experiences booking LH group flights on 016 tickets, I've never had any such issues, and I've always been able to select seats online for LH/OS/LX flights.
Five years ago, buying an LH or LX codeshare could lead to problems with advance seat selection. Those days are now long past. I've flown at least four or five UA issued tickets for flights operated by LH, LX, and OS over the past two years (both native and codeshare flight numbers) and have been 100% successful with advance seat selection. There's virtually no advantage at all to buying on native stock these days (except possibly when buying LX F), particularly with UA offering both better change policies and more user-friendly customer service.