I don't know if I would use the $20 no-name powerheads. I would lean toward a brand like Jebao, which is more in the $50 range for their entry-level powerhead. I wouldn't necessarily call Jebao a "brand name," but they're at least a known entity. As to whether it's "worth it" to buy a $50 Jebao as opposed to a $250 MP10, that's a personal choice. I would personally buy the Jebao every time. I got a used MP10 and it work just fine, but I also have two Jebao PP-4s which have been running for 9 months and 18 months without issue.
There's no doubt an MP10 is higher quality than the equivalent Jebao (at 5 times the price, it better be higher quality). The MP10 will probably last longer as well. To me though, those are intangible "feel good" qualities. Ecotech has a reputation for quality, but how does that translate into real-world reliability? At the end of the day, Ecotech offers a one year warranty on their pumps. If your Vortech fails outside that one year warranty, you're hosed. Do many Ecotech pumps last longer than one year? Sure. Is that a guarantee? No way. To me, it doesn't matter that many people believe that "Ecotech" is a byword for quality: Ecotech tells me the longest that they're willing to guarantee their pumps is one year. That's too short for me, especially when they cost 5 times as much as the competing bargain pump.
Let's say your Jebao pump fails in 6 months and you have to buy another. You've still only spent $100 total ($50 on the first pump, $50 on the second), as opposed to the MP10 which cost $250. If we're pessimistic and assume the MP10 fails after one year, you would have come out ahead buying the Jebaos as opposed to the Vortechs. Let's assume that the MP10 has a more reasonable life of three years. Let's also assume the Jebao pumps have a relatively poor lifespan of 6 months. In three years, you will have bought 6 Jebaos for a total of $300. So even if your MP10 has a relatively good service life of three years and the Jebaos have a relatively bad service life of 6 months, you're still about breaking even by buying the Jebaos. And that's assuming that absolutely nothing goes wrong with your Vortech. If it does, the math is skewed even more in favor of the Jebaos. Plus, Jebaos seem to be hit or miss. If it fails, it'll fail in the first 6 months or so. If it doesn't, it will last a few years. So while you may get a dud that dies after 6 months, you might get one of the good ones that lasts a few years.
To each his own. At the end of the day, this is a hobby, and if aesthetics are incredibly important to you, then Vortechs might make the most sense. For me personally, value is the top priority. Every dollar I don't spend on equipment I can spend on livestock (or one of my other non-reefing hobbies). If Vortech pumps were guaranteed to last three years, the math would work out in their favor and I might never buy a Jebao again. Unfortunately, the longest they're guaranteed to last is one year. When you consider their cost and the cost of Jebaos, I can't justify the price of Ecotech pumps.