Choosing any tool it helps to have an idea about what it's going to be used for and the budget. 'Hobby' covers everything between roughish experimental metalworking and winning an exhibition gold medal. I work almost exclusively in metric, others exclusively in imperial, and others in both.
Expectations may be a problem if you are used to tool-room machines! Hobbyists rich enough to buy new in that category are almost unknown. Trouble is, having been spoilt rotten by working on the best machines money can buy, a hobby lathe might be a severe culture shock. New Far Eastern lathes for the hobby market are capable but not ideal for sustained hard-work. They are crudely finished compared with much more expensive Western equipment. They may lack convenience features or require adjustments that slow down your rate of work. Are you the type who makes the best of an affordable machine, or are you the type who can't cope with imperfections? ("Can't cope" covers everything between time-is-money engineering and being a fuss-pot : as it's perfectly reasonable to be a fuss-pot don't ruin your hobby by buying something you might hate.)
If you can't get to an exhibition, try visiting a local Machine-Mart. They usually have a mini-lathe on display.
How happy are you buying and moving heavy second-hand machine tools? I think it's essential to inspect second-hand machines first. Do you know how to spot junk or machines that will be hideously expensive to repair or difficult to adapt to a home workshop? It's not easy and mostly your problem if you buy unwisely. The advantage of buying new from a reputable supplier if they return your money if the deal goes sour.
Next problem is the size of work you intend. Good advice is to buy the biggest lathe you can afford because big lathes do small jobs and small lathes can't do big ones.
A mini-lathe has about 80% of the capacity of a Myford 7, but it's quiet and just about light enough to be used on a dining table. Suits light modelling and general work well. Myfords are – I think – probably too small if your interest is motorbikes, but OK for smaller gauge locomotives. As you've spotted, the worst aspect of Myford kit is it attracts premium prices. There are good and bad reasons for this. Personally I would look more seriously at alternatives, back in the day hobbyists bought Myford because they were affordable – Boxford and similar started at twice the price and up. Today, these higher specified lathes are in the same price bracket or cheaper. Excellent value if you can find a good one, and many are.
I started with a mini-lathe, learned a lot from it and had fun. After a few years I knew what was wrong with it – no slots in the top slide, awkward gear changing, tricky to adjust top-slide backlash, slide not powered, speed hi-lo lever at the back, and – by far most seriously – it was too small for about 30% of what I was doing. I upgraded to a WM280 which is rather larger than a Myford, and the biggest I could get into my single-garage workshop alongside a Bench, Milling Machine, Band Saw and Junk Box.
Now I know what's "wrong" with a WM280 – for example, a clutch would be nice, and a comprehensive gearbox – and I would be much more confident buying second-hand. But – for what I do – the lathe's shortcomings are trivial. I'm unlikely to change it.
My main regret about buying a lathe was not getting on with it! Once I had one, I regretted the time wasted while I dithered about buying new vs second-hand.
Dave