I recently took a sewing class by a very experienced seamstress who says the Brother 1043D is the best bet.. I used hers in class and it worked fine but honestly I didn't have to thread it. We used home decor fabrics and it was a breeze.. another poster already shows it's about $200 on amazon. Having said that - my husband bought me the Juki that has the air threader and digital settings. I've serged through multiple layers of pleather (is that a word?), minky, knits, home decor, etc.. It's definitely a bit more solid of a machine with lots of fancy bells & whistles that make me feel more confident (as a beginner) to operate it but I wouldn't say it's necessary - $1,000 price tag.
I think it really depends on what you're intending to use it for and how much use will it get? I think most folks buy a serger intending it to last for years, decades, etc.. So buy what you think you'll need to last.
Good luck finding what works best for you!