Now I know what the vociferous reaction of 95% of you will be to that question, but at least hear me out. Here are a few points that may not have been given sufficient consideration yet...
1) Before the election, we assumed that any government that emerged would be vulnerable to ambush because of its arithmetical position in the Commons, where we knew the SNP would be strong. But the outcome last Thursday has turned expectations on their heads. While there will still be opportunities for the SNP to help put together an anti-government majority in the Commons on issues which provoke a Tory rebellion (possibly including repeal of the Human Rights Act), on other issues the heart of the action is more likely to be in the Lords, where the government has just lost its commanding position due to the Tories and Lib Dems parting ways. If the SNP are not even represented in the Lords, they could find themselves sidelined as Labour and a born-again left-wing Lib Dem group under Tim Farron inflict repeated defeats on the Tories. The Lib Dems in particular are now obscenely over-represented in the upper chamber.
2) The only opportunities to get 'hostile amendments' to the Smith proposals passed will probably be in the Lords. If the SNP aren't even in the chamber to table the amendments they want, a huge potential tactical advantage will be squandered. It's true that we have hopes of the government accepting amendments in the Commons, but if that happens it'll probably be because Cameron does it voluntarily, and not because he's forced to.
3) The Lords will be the best chance of preventing EVEL from unfairly disadvantaging Scotland. An SNP group would be able to make common cause with Labour, who still have a vested interest in stopping the Tories becoming stronger via England-only votes.
4) Nicola Sturgeon has repeatedly stressed that we don't want Scotland to be part of the Westminster system, but that for as long as it is, it's vital that Scotland's voice is heard. The Tory win last week takes Lords reform off the agenda, so as things stand, the voice of 50% of the Scottish population will go totally unheard in one of the two chambers of parliament.
5) This is no longer a debate about symbolism or tokenism. If the SNP were willing to take up seats in the Lords, they wouldn't just be getting one or two - with 9% of the seats in the Commons, and 5% of the Britain-wide popular vote, it's hard to see how Cameron could deny them a decent number of peerages. That might be enough to hold the balance in a lot of votes.
6) There is a semi-precedent - a few years ago, Plaid Cymru allowed their former leader Dafydd Elis-Thomas to take up a seat in the Lords.