Yeah that is a quandary. So many choices out there. There are high end, and bargain priced. To the above suggestions, I’d also Airfix, who have done some new tool Emil’s recently, and their old Friedrich is not half bad either. Revell did a nice G-10 that has aged well. The old Otaki/Arii G-6 that has been reboxed by AMT and Airfix is decent if you can find it not overpriced. Eduard has been doing a beautiful family of 109s. Hasegawa has a very good line up too. Fujimi offers a few versions that are certainly worth a look, although it’s a good idea to shop around price wise on these. ICM and Zvezda also offer some new tool kits that should also be up for consideration. Hobbyboss recently tooled some “Easy Build” 109s, But I’ve never seen one opened, let alone built, so I can’t say anything one way or the other...
So, long story short, depending upon the version, if you want a high end kit and money is no object, I recommend Tamiya or Eduard. Eduard Profipack or Masterclass if you want all the goodies in one box. For a bargain kit, go Airfix, Revell, Eduard Weekend Edition, or Hobbycraft.
There are just too many variables for 1/48 109s to say “get THIS kit!”