Simply by using the proper care with bagseed you can make it way better just by simply removing the males and Properly flushing/curing/drying. You can take bagseed and make it better to a certain extent. If a female is pollinated it stops takes energy away from bud development and resin development ultimately making it a bit weaker potency wise and a smaller yield since its trying to make seeds. Take your bagseed, remove the males before they pollinate and you instantly have better weed than what you purchased to get the bagseed.
You should do it in the phases..Keep in mind, you can go 12/12 from seed if you're impatient,etc keep in mind with bagseed you must identify rather its sativa or indica. Full on sativas are much taller and explode in the flowering stage. A problem for indoors. I read and saw a post on a forum a long time ago about how he didn't know it was sativa and he gave it a long ass veg time..then flowered..Went all the way up to his ceiling and he was unable to get the lights in..Was pretty LOL worthy tbh.
1) Bag seed (2-3 grows hoping you actually run into a problem or two so you can identify and fix it) Just want to get from seed to harvest to cover the cost of your setup.
2) Cheap genetics from a decent seedbank Nirvana or Mandala. Which this you know exactly which strain you're getting. Learn cloning and breeding..Do several harvest. Where you keep a mother, clones,etc. Or have a male knock up females to get you more seeds.
3) Once you have enough experience, ran into some problems where you KNOW how to fix those problems fork out the money to get awesome genetic seeds. If you're not going to be running a mother plant, or breed a male and female with good seeds, then don't waste your time on expensive good genetics. The point of spending 100+ dollars on awesome seeds is to have a mother plant to constantly take clones off of her, or hope you get a male and then pollinate a whole crop so you instantly get 300+ dollars worth of seeds.
Dont try bag seed, if a male goes unnoticed it could pollinate your whole crop.
Thats kind of silly, using bagseeds are no more probable than buying 10 regular seeds from a seed bank. You'll still have a 50/50 chance of it either being a male or female. More importantly, he needs to learn how to identify hermies/males/females. If he were to buy 5 fem seeds thinking they would 100% be female he would ignore their sex..then tada guess what, his whole crop got pollinated.
Buying 10 reg seeds from a seedbank will not give you a higher chance of having all females, and using bagseed will not give you a higher chance at having all males. Buying fem seeds you risk it turning hermie from stressing it, or the small slight chance of it actually being a male.
Hence why its not advised for beginners to use fem seeds, as stressing could cause it to hermie.
Bag seed is by far the best, most logical choice to start out with UNLESS you just have the money to burn. Then at the very least start with cheap genetics. The 100+ dollars you spend on good seeds could of went towards more or better equipment.