Convince me not to run extra turn spells

Hello everybody!

I am currently experimenting with the spellslinger archetype and am pretty happy with the results - the decks I build run pretty smoothly and I like the interactivity and the many moving pieces quite a lot...yet I do feel that I kinda lack a real finisher once I managed to build a decent boardstate - the game has just gotten a little too fast for the big gamewinning spells of yesteryear, so to speak and pingers or token creators can win games, but are also pretty vulnerable to boardwipes and draw a lot of aggro due to their AoE nature.

Enter extra turn spells...evaluating them I kinda feel like they are a spellslinger's overrun effects...build a threatening board, drop one of those badboys and just win on your extra turn.

However, I do know that these cards seem to not be well-liked by a lot of players, and whilst they do get played in my playgroup from time to time, they are usually met with frowning. Given the pretty hefty pricetag on the better ones, I wanted to hear some arguments against them to see if they can convince me not to run them.

In my playgroup, the main argument seems to be turn/time economy, which never really convinced me, given that there are a lot of archetypes like Landfall or Aristocrats who can take very long turns, yet are universually accepted.

Tl;dr: Playing [[Temporal Manipulation]] or [[Time Stretch]] as a wincon in a spellslinger deck is no different from playing [[Overwhelming Stampede]] or [[Craterhoof]] in a creature based deck...Am I right?

Edit: thank you everyone for all your feedback - the main takeaway for me was that it's less about taking extra turns per se and more about respecting everyone's time. If you want to use extra turn spells, make sure you actually do go for the win and not just play them for value or mindlessly chaining them together in the hopes of finding a wincon...also know your deck and your gameplan well enough to play out your additional turn(s) as fast as possible.