Ruben123 - It seems to depend on whether folk want "everything automatic", and on how much money they have to spend.
Pentax has by far the largest selection of Film-SLR lenses that will work on the current Digital-SLR bodies.
I'm about to buy my first DSLR, and I'm on a low fixed (pension) income. So I want quality, and "best bang for the bucks". That did look like Pentax K-X, but now that changes to K-R. The K-R retains the good low-light, high-ISO abilities of the K-X, but has improvements, such as focusing screen and now 6fps continuous shooting.
While the standard Pentax 18-55mm kit lens is quite good to start with, I'll be going for a kit-pricing deal with the Sigma 17-70mm, and costs little more - that's not a "Pro" level lens, but it gets good Reviews as a consumer level "walk-around" general purpose lens. It's an f/2.8-4.5 lens with a Macro function. The standard Pentax 18-55mm is f/3.5-5.6 without Macro function.
However, my "50-55mm" prime will be a 1973 Takumar (Asahi-Pentax) SMC f/1.8 55mm. On the modern digital crop bodies, that's 35mm equivalent to 82.5mm, so in the portrait / landscape use range. The range is f/1.8 to f/16, and it has an infinity setting. On the modern bodies, it's preset aperture, and the camera does stop-down for metering. Focus is of course manual.
According to experienced users, the lens is slightly 'soft' at f/1.8 and f/2 - which can suit portrait use, but very sharp when stopped-down, and for that, best between f/4 and f/8. My example was given to me by my landlord, with a camera and other lenses he was given in the 1970s, but never learned to use - so is in unused condition. They can be bought for $40-80.00, depending on condition.
There are other versions, including f/2, f/1.7 and f/1.4 in the Takumar 50/55mm lenses, but the 1973 SMC f/1.8 (the f/2 was the kit-lens of the era) is regarded as being a "best-of" version.
That's an M42 screw-mount lens, and there's a large range of those around - at present I'm looking for the best-of-version 1972/3 Takumar SMC-series Model-2 f/2.5 135mm (the one with 6 elements in 6 groups, not the earlier 5/4 version.) These go for $70-120.00 depending on condition. For that you get a 135mm prime with very good optics that works as an f/2.5 202mm on current bodies. To buy a modern "automatic" all-metal construction f/2.5 135mm prime with as-good optics, you'll pay rather more than $120.00...
And if you don't like M42 screw-mount - there are still a lot of 1990s and early-2000s K-mount (no adaptor needed) lenses around. I have a Sigma 28-80mm (consumer grade, but "reasonable quality), and "the worst lens Sigma ever made" - the 100-300mm f/4.5-6.7 DL - said to give "usable images under good conditions". Interesting - and will "make-do" until I can afford the current Pentax ED 55-300mm - $670.00, here in Sydney.
Those last 2 lenses I bought on Gumtree (a local sales / auction site) - along with an excellent "Antler" brand 2-bodies and 4 lenses bag, a Pentax F-SLR body - in a bundle for $60.00. The as-new bag is worth more than that. But if you said, 4 items at $15.00 each - and the lenses are "usable" - that's pretty economical.
Still - some will want the "modern and fully-automatic-everything" lenses - and they're more convenient for those who can afford a decent collection of them.