Performing the following (note the range of 10,000):

`importmulti '[{"desc": "sh(wpkh([aeee1e6a/49h/1h/0h]tpubDC5bVdaveQYxGFztMShFAjU637kKjrs9FD8ne1oHR7z8tLeQJExsaxWRVeSpcCcYMdp5ecf2LQhuVaeYFZ7YEpvWTJr4nDGUJrmuvLuTSsp/1/*))", "keypool": true, "timestamp": "now", "watchonly": true, "internal": true, "range": {"end": 1000}}]' '{"rescan": false}'`

takes many minutes. @achow101 reports a similar import taking 6 minutes on his machine.
assert(it != mapWallet.end());
        CWalletTx& wtx = it->second;
        int currentconfirm = wtx.GetDepthInMainChain(locked_chain);
        
        assert(currentconfirm <= 0);
        
        if (currentconfirm == 0 && !wtx.isAbandoned()) {
            
            assert(!wtx.InMempool());
            wtx.nIndex = -1;
            wtx.setAbandoned();
            wtx.MarkDirty();
            batch.WriteTx(wtx);
            NotifyTransactionChanged(this, wtx.GetHash(), CT_UPDATED);
            
            TxSpends::const_iterator iter = mapTxSpends.lower_bound(COutPoint(now, 0));
            while (iter != mapTxSpends.end() && iter->first.hash == now) {
                if (!done.count(iter->second)) {
                    todo.insert(iter->second);
                }
                iter++;
            }
            
            
            MarkInputsDirty(wtx.tx);
        }
    }
    return true;
}
void CWallet::MarkConflicted(const uint256& hashBlock, const uint256& hashTx)